1. Field of the Invention
The invention relates generally to an attenuating element.
2. Description of the Related Art
An attenuating element of this type can be used to attenuate the action of the waves, for example on water-control structures, such as dykes. In addition, the attenuating element according to the present invention can be used for attenuating sound waves, wherein a number of attenuating elements form a sound-attenuating barrier or wall. Other possibilities to attenuate the energy of waves can be achieved by means of attenuating elements, for example the removal of large quantities of water.
In the prior art, series of blocks which have been placed against one another have been used as attenuating elements which are used for dykes, wherein the upper surfaces of such blocks have been placed in a more or less adjoining manner. It has been found that it is possible to achieve an improvement if apertures are provided on the upper side into which the water can be moved. As a result thereof, the flow of the water flowing onto the dyke is disrupted and the attenuating action is increased.
However, in the prior art this requires highly complex elements which are associated with correspondingly high production costs.
US 2002/0025231 discloses an attenuating element assembly consisting of a series of attenuating elements with a common base part. Such a structure is very difficult to install, can certainly not be handled by hand and does not provide a possibility for modifications to the shape of the body located underneath, such as a dyke body or another wall. Due to the common base part, there is no interaction with the remainder of the dyke.
U.S. Pat. No. 5,556,230 discloses a coastal defence system consisting of a number of elements with narrowed and enlarged parts which are placed against one another in turns. Although this does make it possible to follow the shape of a dyke body, it only achieves limited additional attenuation, if any. Such a structure is only suitable for preventing erosion of material.
All structures of this kind have the drawback that they are so heavy that they cannot be readily installed by hand and, in addition, are very difficult to produce from concrete material. More particularly, they require a very complicated mould, as a result of which it is not possible to produce them at high speed and on a large scale at relatively low cost.
WO 03/076727 discloses an ecological block which can be used on river banks and is provided with cavities which are to be filled with vegetation. The block is substantially rectangular and, in a first embodiment, is substantially flat on two opposite sides. In another variant (FIG. 6), one side thereof is flat and the opposite side is provided with a head part and a base part. It is intended to place the flat side against a wall.